The difference between successive discounts of $40 \%$ followed by $30 \%$ and $45 \%$ followed by $20 \%$ on the marked price of an article is $Rs.\,12.$ The marked price of the article is (in $Rs.$)

Surbhi bought a combined total of $25$ i-pads and i-phones. She marked up the i-pad by $20 \%$ on the cost price, while each i-phone was marked up by $Rs.\, 2000.$ She was able to sell $75 \%$ of the i-pads and $2$ i-phones and make a profit of $Rs.$ $49000 .$ The remaining i-pads and $3$ i-phones could not be sold by her. Find her overall profit or loss if she gets no return on unsold items and it is known that an i-phone costs $50 \%$ of an i-pad.

If the selling price of $\frac{2}{3}$ of a certain quantity of milk be equal to the cost price of whole milk, then what will be the gain percent in this transaction?

Oil equal to $20 \%$ of the weight of ground nut is extracted in a mill. The matter left after extraction is sold as cattle feed at the rate of $Rs.\, 12.5$ per $kg$. The ground nuts are bought at $Rs.$ $20$ per $kg.$ the processing cost is $Rs.\, 5$ per $kg$. At what price $(Rs.$ per $kg$ ) should the oil be sold to earn $20 \%$ profit on total costs (Total cost $=$ cost of groundnuts and processing costs)?

A shopkeeper buys $144$ items at $90$ paisa each. On the way $20$ items are broken. He sells the remainder at $RS.\,1.20$ each. His gain percent correct to one place of decimal is

A shopkeeper sold some article at the rate of $Rs.\, 35$ per article and earned profit of $40 \% .$ At what price each article should have been sold so that profit of $60 \%$ was earned. in$Rs.$